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> big 4 engine specs, what to expect?, used motor in 550 spyder, potential?
Dave Avery
post Oct 10 2003, 02:01 PM
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Hey all

sorry for the crosspost to shoptalk, but I thought you guys could shed some light on this too:

I bought this motor used, and it's now in my 550. I'm not sure what to expect from it... I did speak with the mechanic, and he sounds very reputable.

103mm pistons, 75 mm Crank, SCAT connecting rods, Web Cam 86a, Web Cam lifters, H/D valve springs, heads ported and polished with 48mm x 38 mm valves, aluminum valve covers, all new bearings and gaskets, lightened the flywheel, dual Weber 44IDF carbs, Bosch 050 with points. I'm using a holley blue pump with a holley regulator, set to 3.5psi (gauge tapped)

The engine runs very strong, and seems like it's all about 2-4K RPM. There is a stumble if I floor it, but it runs nicely at half throttle. Power drops sharply after said RPM, which leads me to think that either.

1) Weber 44IDF's are choking off high end
2) Timing is way off
3) Webers are way off
4) Porsche 901 has cruiser gearing
5) Gunk in the jets

I would expect this engine to be at around 150-180hp, and in a 550 spyder (1300lbs without me) this thing should be a rocket. I'm pretty happy (esp. for the $2500 I paid for it) but it seems more like a tractor than a rocket (IMG:style_emoticons/default/wink.gif)


So, two questions... 1) What should I expect from this motor powerband wise, and 2) any ideas on making it work better?

This is actually the fun part, after a 3 year buildout (IMG:style_emoticons/default/smile.gif)
Thanks,

-DMA
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Brad Roberts
post Oct 10 2003, 02:11 PM
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We need to know all the jetting and venturi sizing in the carbs. It does sound like its running out of breath on the top end. That cam should pull to 6500... but I dont run it with 48x38...soo..

Lose the points.



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john rogers
post Oct 10 2003, 03:09 PM
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Since I raced with a big four for several years here's my take on it: Get Weber 48's, 44's are too small, loose the points as Brad said, get a head temp and exhaust temp meters and watch them closely and finally set the carbs on a dyno so you won't burn things up. Good luck
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Brad Roberts
post Oct 10 2003, 03:13 PM
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Whoa.. I didnt do the math.. that is a big engine.

I use 48's on anything over 12.5:1 and 2300cc's


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Dave Avery
post Oct 10 2003, 03:14 PM
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Sadly, I had a set of brand new 48 Dells from Jake Raby, and ran out of money so I had to sell them while the car was being built (IMG:style_emoticons/default/sad.gif)

Thanks for your input (IMG:style_emoticons/default/smile.gif)

-DMA
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Brad Roberts
post Oct 10 2003, 03:17 PM
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Did Dell make a 48 ?? I thought they only had a 45... oh well. You can buy new Weber 48 IDA's now.


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mike_the_man
post Oct 10 2003, 03:22 PM
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Dave,

What type of 550 did you get? I'm assuming a replica, but which brand? $2500 sounds like a great deal. Where did you find it? I love the 550s, and I hope to get either a Beck or Vintage in the next few years. I'd love to see some pics, if you have any.
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Dave Avery
post Oct 10 2003, 03:26 PM
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Hi Mike

It's a 2000 Beck... best to visit www.spyderclub.com (I'm the webmaster and a partner ) and peek around the forums there.

This thing is taking way too long, it sorta takes the fun out of things (as does spending nearly 32K). You know, there are days I think I'd trade this thing like *that* for a nice 914v8 or a 911 cab. I miss the driving part of owning a sports car (IMG:style_emoticons/default/wink.gif)

If you get a car, get a Vintage, Beck or Thunder Ranch, and just (IMG:style_emoticons/default/MDB2.gif) it, don't take it apart and try to make a statement.

-DMA
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Brad Roberts
post Oct 10 2003, 03:29 PM
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OH.... Dave.. the ultimate web board SIN. CHANGE the colors from the bone stock rollout..LOL


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mike_the_man
post Oct 10 2003, 03:39 PM
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I've been to www.spyderclub.com a few times. A really good website, with lots of good info. I learned a lot on there. I really hope to get a 550 in the not too distant future. I'd be happy with a stock Beck or Vintage, I just want to use it as a Sunday cruiser.

The only problem with getting one is that I live in Canada, and it seems like it's pretty difficult to import kit cars. I haven't looked into it too much. Made a few calls, got put on hold for 45mins, that sort of thing. Isn't dealing with the Government fun?!? (IMG:style_emoticons/default/finger.gif) Anybody have any experience improrting kit cars to Canada? I'd love to hear about it.
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Dave Avery
post Oct 10 2003, 03:41 PM
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Actually, it's not as easy as with Invision... there are themes you use for the graphics. I actually like the subsilver theme myself (IMG:style_emoticons/default/wink.gif)

The problem is that I've got 7+ mods on the board, all which modify the theme. I'm not really interested in tracing it out at the moment.

It's running on IIS on Win2K (PHP!) and MSSQL 2000. Runs like a top though.

-DMA
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Brad Roberts
post Oct 10 2003, 03:43 PM
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Damn it.. I knew this would run good on a W2K box.

It looks fine.. the site looks good. I'm just razzing you.


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